Transcript Slide 1

Stand by me:
Too much sitting is bad for you, but what
can we do about it?
Stuart Biddle
Professor of Physical Activity & Health
School of Sport, Exercise & Health Sciences
Loughborough University
&
NIHR Leicester-Loughborough Diet, Lifestyle and
Physical Activity Biomedical Research Unit
Is sedentary
behaviour
associated with
health outcomes?
Establish links
between
behaviour
& health
Behavioural epidemiology
framework
What factors are
associated with sedentary
behaviours?
Determinants
or correlates
Interventions
Measure
behaviour
What is sedentary
behaviour and how
do we measure it?
2
Can we change
sedentary
behaviours?
Translation
into
practice
Can we ‘roll
out’ behaviour
change
solutions?
Content today
 Introduction & definition
 Health outcomes
 Behaviour change
3
Introduction and definition
So what is
sedentary
behaviour?
4
Sitting, Sedentary and active behaviours
lying,
very low
EE
Sleep
Sedentary
behaviour
Light
movement
EE
5
Moderate
PA
Physical
activity
research
Vigorous
PA
TV
Computers
Motorised
transport
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Sitting at
school
or work
Screen time
Sedentary
behaviours
Socialising
Homework
Reading;
Listening
to music
Sedentary time per day: US adults by accelerometry
10
9
NHANES N=6,329
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H
r
s
/
d
a
y
7
6
Male
Female
5
4
3
2
1
0
20-29
30-39
40-49
50-59
60-69
70+
Matthews et al: Am J Epi, 2008
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Health outcomes of sedentary behaviour
Is sedentary
behaviour bad
for you?
8
Is sedentary
behaviour
associated with
health outcomes?
Establish links
between
behaviour
& health
 All-cause mortality
 Obesity
 Metabolic health
markers & diabetes risk
 Physical fitness
 Mental health
9
Is sedentary
behaviour
associated with
health outcomes?
Establish links
between
behaviour
& health
 All-cause mortality
 Obesity
 Metabolic health
markers & diabetes risk
 Physical fitness
 Mental health
10
All-cause mortality: Risk ratios for sitting time for adults
2
1.8
1.6
1.4
1.2
Risk of ACM
1
Inactive
Active
0.8
0.6
0.4
0.2
0
1 (Low)
2
3
4
5 (High)
Sitting
Canada Fitness Survey 1981-1993 (Katzmarzyk et al., MSSE, 2009)
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TV viewing and all-cause mortality: Meta-analyses
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Systematic Review and Meta-Analysis
13
14
Is sedentary
behaviour
associated with
health outcomes?
Establish links
between
behaviour
& health
15
 All-cause mortality
 Obesity
 Metabolic health
markers & diabetes risk
 Physical fitness
 Mental health
Risk of overweight/obese by sedentary and PA levels in
Australian adults who are ‘sufficiently active’
2.5
2
Lo SED/Hi PA
Lo SED/Lo PA
Hi SED/Hi PA
Hi SED/Lo PA
1.5
Odds ratio
1
0.5
0
All
Men
Women
(Sugiyama et al., IJBNPA, 2008)
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Risk at 26y from TV viewing at 5-15y
50
45
40
35
30
Prev risk (%) 25
Overweight
Smoking
20
15
10
5
0
<1
Hancox et al.,
The Lancet, 2004
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1-2h
2-3h
TV (Wkd) childhood
>3
Is it sitting or eating, or both?
 Pearson & Biddle (2011). Sedentary behavior
and dietary intake in children, adolescents
and adults: a systematic review. American
Journal of Preventive Medicine, 41(2), 178 –
188
 Children (k=24 independent samples)
 Adolescents (k=72)
 Adults (k=14)
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What about sedentary behaviour and nutrition?
 Key findings:
 Studies show clear associations between
sedentary behaviour (usual screen time, and
often TV viewing) and:
 elements of a less healthy diet including –
lower fruit and vegetable consumption
higher consumption of energy-dense snacks,
drinks and fast foods
higher total energy intake
 Strength of associations: small-to-moderate
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Is sedentary
behaviour
associated with
health outcomes?
Establish links
between
behaviour
& health
20
 All-cause mortality
 Obesity
 Metabolic health
markers & diabetes
risk
 Physical fitness
 Mental health
21
Meta-analysis of sedentary time and metabolic syndrome
 Edwardson et al., (2012). Association of
sedentary behaviour with metabolic
syndrome: a meta-analysis. PLoS ONE, 7(4),
e34916. doi: 10.1371/journal.pone.0034916
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Meta-analysis of sedentary time and metabolic syndrome
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Sedentary behaviour and health outcomes




What might be the mechanisms?
Low EE and weight gain
Unhealthy diet
Metabolic effect of muscle activity required for
standing v sitting
 Clustering of unhealthy risk factors
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Interventions for behaviour change
Can we change
sedentary
behaviour?
25
Sedentary and active behaviour shifts
1
2
Sleep
Sedentary
behaviour
Light
movement
MPA
VPA
PA Guidelines
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Interventions to reduce sedentary behaviour in young people
 Meta-analysis
 K=17 (n=4976)
 Only studies that
specified their primary
goal was to reduce
sedentary behaviour
 All targeted screen time
(Biddle et al., B J Sports Med, 2011)
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Results
 Hedges’ g = -0.19
 A small but significant
effect
 [Maniccia et al,
Pediatrics, 2011:
Hedges’ g = −0.14]
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Conclusions & issues - 1
 Interventions produced small effect
 Is this meaningful? But … what about small
effects across a large population??
 Sedentary behaviour may be difficult to
change
 There may be a strong habitual element
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Conclusions & issues - 2
 Most focus only on children
 Interventions focus on screen-time only
 Intervention fidelity and process evaluations
are lacking
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What kind of interventions are being attempted?
 Example: Education (Gortmaker et al., Arch Pediatr Adolesc
Med, 1999):
 Planet Health programme - curriculum focusing on 4
behaviours inc. reducing TV viewing
 Example: Family-based (Epstein et al., Arch Pediatr
Adolesc Med, 2008)
 Television/video and computer use was monitored
and budgeted by a TV allowance device
Displacement?
Targeted
sedentary
behaviour
Non-targeted
sedentary
behaviours
Physical
activity
Are workplace interventions to reduce sitting effective?
 6 studies met the inclusion criteria (5
randomised trials and one pre–post study)
 The primary aim of all 6 was to increase
physical activity
 All had reducing sitting as a secondary aim
Are workplace interventions to reduce sitting effective?
 Conclusion:
 “While reducing sitting time is emerging as a
new workplace-health priority, there is
currently a lack of evidence to show that
workplace interventions for reducing sitting
are effective”
Emerging evidence with adults
 Australian adults aged 60 years and over
 45 minute face-to-face meeting to assist participants in
reducing their sitting time and to increase their breaks in
sitting
 Various strategies offered, including goal setting and selfmonitoring
 Sedentary time was reduced by 3.2% (~20 mins)
 Number of breaks from daily sedentary time increased
 Time spent in light and moderate-to-vigorous physical activity
increased
 Participants reduced their sedentary time mainly between
10.00h-21.00h, and increased their breaks in sedentary time
after 19.00h.
Gardiner et al., Am J Prev Med 2011
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Behavioural Choice Theory for Sedentary Behaviour
Environmental
Modifiers
Reinforcement
value
Access/
availability
Behavioural
Choice:
Sedentary
Behaviour
Need to promote MORE PA and LESS sedentary behaviour
 ‘Sedentary behaviour’ is “new” and needs
greater attention
 Need to think about it differently (from PA)
 Ubiquitous
 Habitual
 Reinforcing
 Cultural and environmental shifts required!
 Do we need to be standing ‘all or most of the
time’ or just breaking up prolonged sitting?
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What’s possible?
At work
At home




 TV restrictions
 Habit breaking (needs
prompts and
environmental change)
 Alternative activities
 Goals and self-monitoring
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Standing/modified desks
Screen prompts
Standing meetings
Regular standing breaks
Challenges and Opportunities




Convergent technology
Mobile technology
Technology is not going away
Create rules and time budgets for sedentary
technology use
 How can we use technology to promote and
support behaviour change?
 How can we break the dependence on doorto-door car travel?
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Bottom Line
 ‘Move more, sit less’!
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Stand by me:
Too much sitting is bad for you, but what
can we do about it?
Stuart Biddle
Email: [email protected]
Twitter: @stuart_biddle